wrote:

Hi - thought I'd ley you know, I'm the guy who writes the
middlesexcountycouncil website. The green lane you describe is a 42
and 48 inch watermain built early in the 20th Century to link the new
river water company with the Hampton system. It does run east beyond
Cricklewood. If you go to

http://middlesexcountycouncil.org.uk...d=17&Itemid=35

and scroll down there are 4 or 5 pages describing the route stage by
stage from the viewpoint of a walker.

He mentions a reservoir in Golders Green... where is it?

Also one in West Hampstead.... is that the thing inside Gondar Gardens?